In recent years, compelling evidence has emerged about the growing resistance to drugs in microbes and the rise of the so-called “superbugs.” Now, a new study published in the journal Nature Genetics says that a “major global threat” is emerging in parts of Asia and Africa, where a form of antibiotic-resistant typhoid is rapidly displacing other strains.
“Multidrug-resistant typhoid has been coming and going since the 1970s and is caused by the bacteria picking up novel antimicrobial resistance genes, which are usually lost when we switch to a new drug,” Kathryn Holt from the University of Melbourne and one of the study's authors, reportedly said. However, in the new strain -- named H58 -- these genes are fast becoming a stable part of the bacteria’s genome.
“Multidrug resistant H58 has spread across Asia and Africa over the last 30 years, completely transforming the genetic make-up of the disease and creating a previously underappreciated and on-going epidemic,” Holt said in a statement released Tuesday.
Typhoid is contracted by drinking or eating contaminated matter and its symptoms include nausea, fever, abdominal pain and rose-colored spots on the chest. Salmonella typhi, the bacteria that causes the disease, is currently believed to infect nearly 30 million people worldwide -- most of who live in developing or underdeveloped Asian and African nations.
While vaccines are available, and can prevent about 50 percent to 70 percent of the cases, their use is not widespread. Most people rely on antibiotics to treat the infection -- a practice that is resulting in the rise of the Multidrug-Resistant (MDR) strain.
According to the study, of the over 1,800 bacterial samples obtained from 63 countries between 1992 and 2013, 853, or 47 percent, belonged to the H58 strain. The strain was found to be present in 21 countries.
“H58 is an example of an emerging multiple drug resistant pathogen which is rapidly spreading around the world,” Holt said in the statement, adding that “effective vaccine strategies” instead of indiscriminate use of antibiotics was needed to curb the spread of the disease.
The latest research comes just months after a British government-commissioned review warned that the rise of superbugs could cast medicine “back to the dark ages” and lead to the deaths of over 10 million people annually by 2050. “Drug-resistant bacteria know no borders,” the researchers of the previous study said at the time.